Depression is common but frequently undetected and untreated among medical patients, leading to significant decrements in functioning and quality of life. Low-income minorities may be especially prone to suffer from both depression and physical illness, while being less likely to receive care for either. Quality improvement interventions for depression in primary care have led to better care and outcomes, but are often costly and difficult to sustain, especially in resource-poor health systems. Additionally, although referred by most patients, psychotherapy is particularly difficult to deliver in the medical sector. Developing an effective, low-cost, sustainable, culturally relevant, psychosocial treatment for primary care patients with depression and chronic medical illness is thus an important public health goal. We propose to use a theoretically driven, systematic method for adapting group self-management programs developed and proven effective for persons with chronic medical illness for patients who also have depression. First, we use two existing high quality datasets of group self-management trials (the Chronic Disease Self-Management Program (CDSMP) and the Spanish Arthritis Self-Management Program (SASMP)), to examine the depression and medical outcomes of patients with comorbid conditions and to explore predictors of response and intervention mechanisms, guided by an adapted conceptual model of the interactions between depression and medical illness. Second, guided by these results, we collect qualitative data from depressed persons in ongoing self-management groups and their group leaders to explore their unmet needs and potential program adaptations. Third, an expert panel uses study findings to adapt the programs as necessary and develops a manualized program protocol in preparation for a future randomized trial. [unreadable] [unreadable]